I really don't know what he did. At first I thought that he'd been bitten by his field mate, although it seemed like a weird place. But the vet said that she would have expected to see much deeper tissue damage if he'd been bittent there because of how the offender would have had to grip him to make such a hole - if that makes sense. So, can only think that he may have had his head down and suddenly lifted it, not realising that there was something (maybe hawthorn?) immediately above him. Mind you, isn't it typical, he has a big open field and the only hawthorn is right at the edge where there is hardly any grass anyway!!!!!! Horses - you could put them in a straigh jacket in a carboard box and they'd still hurt themselves. So he had a dreadful hole at the base of his ear.